Internal combustion engine



Sept. 15, 1936. MCPHERSQN 2,054,133

INTERNAL COMBUST ION ENGIN E Original Filed May 29, 1930 5 Sheets-Sheetl Sept. 15, 1936. L MnPHERSON 2,054,133

INTERNAL COMBUSTION ENGINE Original Filed May 29, 1930 5 Sheets-Sheet 2Sept. 15, 1936. H. MCPHERSON 2,954,133

INTERNAL COMBUSTION- ENGINE Original Filed May 29, 1950 5 Sheets-Sheet 3iv/a'lvra 460 1179591 W lf/YE) Sept. 15; 1936. H. MCPHERSON 2,054,133

INTERNAL COMBUSTION ENGINE Original Filed May 29, 1950 5 Sheets-Sheet 428 I37 7 [AWE/v70 .fld/ 4477407 Sept. 15, 1936.

H. L. M PHERSON INTERNAL COMBUSTION ENGINE Original Filed May 29, 1930 5Sheets-Shget 5 fero'ap Patented Sept. 15, 1936 INTERNAL COMBUSTIONENGINE Barry L. McPherson, Memphis, Tenn.

Application May 29, 1930, Serial No. 456,890 Renewed March 24, 1934 6Claims.

This invention relates to internal combustion engines, particularly ofthe air cooled radial type ordinarily used for airplanes, and hasparticular reference to the cooling systems of such motors.

The objects of the invention are:

(a) To provide means for minimizing the air resistance of such an enginefor airplane service;

(b) To provide an improved cooling system for such an engineparticularly for airplane service; and

(c) To generally improve the details of design and construction of suchan engine.

The means by which the foregoing and other objects are accomplished andthe manner of their accomplishment will readily be understood from thefollowing specification'on reference to the accompanying drawings inwhich:--

Fig. 1 is a sectional elevation of the device at right angles to thecrank shaft and on the center line of the cylinders, being taken as onthe line II of Fig. 2,-looking in the direction of the arrow.

Fig. 2 is a longitudinal sectional elevation taken as on the line IIIIof Fig. 1, same. being on the center line of the crank shaft and pin andalso of a pair of cylinders.

Fig. 3 is a section similar to that of Fig. 2, with the cylinders andcrank shaft shown in elevation,

Each'air cylinder is connected with its respective power cylinder as bya pipe or tube I2. All the cylinders are provided with the usual pistonsI3 and connecting rods, and being of the single row radial type have acommon crank pin It. Preferably the connecting rod I5 of one of the aircylinders is a master rod, with the other rods It, pin connectedthereto, while the rods I! for the power cylinders are of the slippertype. 22 is the engine shaft which extends forwardly in usual manner tocarry the usual propeller, not shown.

Cooling system V I25 is a sheet metal casing 01' cowl substantially domeshaped, with the axis of the dome coincident with the shaft axis. Theapex of the dome is forward and is apertured to permit the engine shaft22 to extend forward through such aperture. and carry the propeller. Thecasing enlarges rearwardly to enclose the air cylinders Ill includingthe head and valves thereof. In order to permit access to thesecylinders a portion I26 of the cowl is detached from the remainderthereof and made-a part of the head of the cylinder. From this head finsI21 extend to and are integral with the cut-out section and beyond thissection continuations I28 of thesefins extend outward. Cooling of thehead of the air cylinders is thus accomplished, with minimum airresistance.

Adjacent the forward end of the cowl, an annular depression I29 isformed therein, in which depression an annular exhaust manifold I30 isdisposed. The forward surface I3I of this ring is shaped to conform tothe dome contour, whereas the rear portion I32 thereof is shaped toconform to the depression I29. This rear portion however is spaced awayfrom the depression so that an annular air passage I33 is formedtherebetween. a

From each exhaust port I9 of the power cylinders, pipes I34 extendforwardly and discharge into the manifold 'I 30, duplicate exhaust pipesbeing thus provided for each power cylinder. The pair of exhaust pipesfor each cylinder is preferably held in place thereagainst by bolts I35.Exhaust pipes I3! lead rearwardly from the ex haust ring preferably indepressed channel-ways I38 in the exterior of the cowl.

Each of the power cylinders is provided with a plurality of radial fins139 which extend out to and are integral with a stream lined casing I40and beyond which casing continuations I4I of these fins extend. Thecasing I40 is tangent to and may form a part of the wall of the cylinderat the sides thereof,-so that at such point only the extensions MI 'ofthe fins occur. Preferably the fin extensions beyond the casing, infront and at the rear of the cylinder, are of less extent than those atthe side thereof, ordinarily being almost negligible. The cowl isinterrupted immediately in front of each of these fin structures, and achannel-way leads rearwardly therefrom past and dividing around eachcylinder and its fin structure. The radially-inner wall N2 of thispassageway extends rearwardly substantially at right angles to the powercylinder and radially inward from the lower fins thereof until after thefin structure is passed after which it curves outward to again join thecowl. The side walls I43 of this passageway closely embrace the finstructure on the opposite sides of the cylinder, and may be integralwith the fin structure. These walls are brought closer togetherforwardly and rearwardly from the cylinders, and are joined at the outerend of the cylinders by a radially-outer wall I44, substantiallyparallel with the inner wall I42. A stream lined cap I45 secured to thisouter wall may be used to enclose the valve structure.

This structure presents as far as possible a stream line front tofacilitate airflow when used for airplane service, and it directscooling air past the cylinders with a minimum of resistance. Withslightly more than normal fin thickness,

heat is radiated to the fin casing wall and the fin extensions, and iseasily brought into contact with the air, this being true as well,- ofthat part of the fins which lie immediately in the rear of the cylindersin what is known as the hot zone where failure of air cooling firstoccurs. cooling advantage is taken of the casing wall and also, whereintegral with the fins, of the passageway walls.

Having described my invention, what I claim is:

l. A radial, air cooled, aircraft engine, said engine includingcylinders having parts carried by and extending beyond the headsthereof, and having cooling fins, a cowl of substantially streamlineexternal configuration around said engine, including said head carriedparts, and preventing radial airfiow in the zone of the cylinders ofsaid engine, said cowl having openings for entrance and exit of coolingair, such openings being a substantial distance forward and rearwardrespectively from the center lines of the cylinders of said engine so asto minimize eddy formation by said cylinders, means disposed betweensaid cylinder heads and said cowl substan-' tially preventing air flowpast said parts, and means, cooperating with said first means and saidcowl,.to confine substantially the entire flow of said coolingainbetween the cooling fins of said cylinders.

2. The combination with an airplane engine having radial cylinders, saidcylinders having valve parts extending beyond the heads thereof andhaving heat radiating fins, of a housing of substantially streamlineexternal configuration, surrounding said engine, including the cylindersand valve parts, said housing having air entrance and exit openingsrespectively forward and rearward of the zone of said cylinders meanswithin said housing enclosing said valve parts, and means within saidhousing, cooperating with said valve enclosing means and lying betweenthe cylinders for substantially constraining all air entering saidhousing to fiow between said fins.

3. A radial, air. cooled, aircraft engine having cylinder-head-carriedvalve parts extending beyond said heads, an externally substantiallystreamlined housing preventing radial air fiow near the cylinders ofsaid engine, said housing In this being open in front and rear of thezone of said cylinders to permit internal air flow, means extendingrearwardly from said front openingto said rear opening and cooperatingwith said housing to enclose said valve parts, and means coop eratingwith said first means to direct air flow through said housing in adirection transverse to the cylinders and to substantially confine suchflow to the spaces adjacent said cylinders.

4. The combination with an air cooled aircraft engine having radialcylinders with cylinderhead-carried parts extending beyond said heads,said cylinders, including the heads thereof, having heat radiating fins,of a housing of substan:

tially streamlined external configuration surrounding said engine,including said cylinders and head carried parts, said housing having airentrance and exit openings directly forward and rearward respectively ofthe zone of said cylinders and means within said housing for restrictingthe area of opening around said cylinders so as to cause .the flow ofair entering and passing through said housing to be substantiallyconfined to the spaces between said fins.

5. The combination with an air cooled aircraft engine having radialcylinders with cylinderhead-carried parts extending beyond said heads,

said cylinders, including the heads thereof, hav-' 1 ing heat radiatingsurfaces, of a substantially streamlined housing surrounding saidengine, including said cylinders and head carried parts, said housinghaving air entrance and exit openings directly forward and rearwardrespectively of the zone of said cylinders and means within said housingfor controlling the flow of air through said entrance openings and saidhousing by restricting the areav of opening around said cylinders so asto confine air flowthrough said housing to the spaces immediatelyadjacent the heat radiating surfaces of said cylinders.

6. In an air cooled aircraft engine, having radial cylinders, with partscarried by and extending beyond the heads thereof, said cylinders havingannular, radially disposed heat radiating fins, a housing concentricwith the shaft of said engine, apertured to permit said shaft to extendforwardly to receive a propeller, said housing having openings, one infront of each of said cylinders, and passageways leading rearwardly fromsaid openings to and past said cylinders; each of said passagewayshaving an outer wall lying adjacent, and substantially parallel with thefins of its said cylinder, and cooperating with said housing to enclosethe said headcarried parts,

and side wall portions substantially contactingv the peripheral edges'of the fins of ,said cylinder strain air entering said openings to flowbetween 60 said fins.

- HARRY L. McPI-IERSON.

